In:
Population Ecology, Wiley, Vol. 35, No. 2 ( 1993-12), p. 199-213
Abstract:
Long‐term variation in recruitment was estimated by constructing projection matrices for a marine bivalve, Yoldia notabilis , at two stations in Otsuchi Bay, northeastern Japan, and the effects of its variation on population dynamics were examined using a simple matrix model. The matrix model was developed from the Leslie matrix, in which the population growth rate λ was expressed as a function of recruitment rate r 0 . The equilibrium recruitment rate r s , or the recruitment rate required to maintain population at constant size (λ=1), was expressed by the reciprocal of the reproductive value of a newly recruited individual. The estimates of r s for the field population were lower at the shallower station than at the deeper station, reflecting higher survivorship and fecundity. Past recruitment rate estimated both by the field samplings for 3 years and by the back‐calculation from the current age structure for over 10 years showed large yearly variation, ranging between 0 and 58.6×10 −4 . The estimates were larger than r s , and hence, large enough to increase population size (λ 〉 1) only in approximately one‐third of the estimated years. This suggests that the population has been maintained by occasional successful recruitment occurring once every few years.
Type of Medium:
Online Resource
ISSN:
1438-3896
,
1438-390X
Language:
English
Publisher:
Wiley
Publication Date:
1993
detail.hit.zdb_id:
1474902-6
SSG:
12
Permalink